The Effects of Sugarcane Aphid Density in Sorghum on Predation by Lady Beetles and Lacewings

Publication date: Available online 25 October 2018Source: Biological ControlAuthor(s): Jeremy Hewlett, Adrianna Szczepaniec, Micky D. EubanksAbstractThe sugarcane aphid, Melanaphis sacchari Zehntner (Hemiptera: Aphididae), is a new and devastating pest of sorghum (Sorghum bicolor (L.)) in the United States. Arthropod predators, especially lady beetles and green lacewings, are often abundant in sugarcane aphid-infested sorghum, but little is known about the effects of these predators on sugarcane aphid populations. We quantified the effect of two species of lady beetles (larvae and adults of Coccinella septempunctata L. and Harmonia axyridis Pallas) (Coleoptera: Coccinellidae) and green lacewings (larvae of Chrysoperla rufilabris Burmeister) (Neuroptera: Chrysopidae) on aphid colony growth across several aphid densities (20, 40, 80, 160). We found that all predator species and life stages significantly reduced the growth of sugarcane aphid populations at low to intermediate aphid densities (20, 40, and 80 aphids per colony). At the highest aphid density (160 aphids), however, H. axyridis larvae were much less effective than C. septempunctata larvae and adults and H. axyridis adults and lacewing larvae did not suppress sugarcane aphid colony growth. We incorporated these predator effects into a dynamic predator-prey model to predict the impact of predators on the short-term population dynamics of sugarcane aphids in sorghum (2 to 14 days) and the ability of these predators to s...
Source: Biological Control - Category: Biology Source Type: research